Molecular assembly method and application of an organic D-A type multi-valued conjugated small molecule

Abstract

The present invention discloses a molecular assembly method of an organic D-A type multi-valued conjugated small molecule. The steps are as follows: Using 1,2-diaminobenzene and oxalic acid as raw materials, and polyphosphoric acid as a catalyst, reacting in an alcohol solvent. After the reaction is completed, it is cooled, filtered by suction, washed, and dried under vacuum to prepare a brown powdery solid, namely the organic D-A type multi-valued conjugated small molecule; dispersing the prepared molecular material in an organic solvent, completely dissolving it to form a clear and transparent solution to obtain an assembly solution; dropping the prepared assembly solution on the surface of a clean indium tin oxide glass, standing still, and waiting for the solvent to slowly volatilize naturally until the surface of the indium tin oxide glass is dry to obtain an assembly, and providing an application of the said assembly as ultra-high density information storage. The small molecule material of the present invention can achieve ternary information storage performance, and the prepared assembly can further improve the information storage density of the device to achieve ultra-high density information storage.

Description

Technical Field

[0001] The present invention belongs to the fields of functional semiconductor materials and electronic information, and relates to a method for synthesizing and molecular self-assembling an organic D-A type functional small molecule semiconductor material, and its application in the field of ultra-high density information storage. Background Art

[0002] Existing information storage technologies can no longer meet the storage requirements, so scientists are developing new technologies to store this vast amount of data. So far, scientists have proposed two strategies: one is to continuously reduce the size of silicon-based storage units to improve their storage density; the other is to develop multi-valued information storage materials and devices, so that their storage density can be increased from 2 n to 3 n . However, compared with the strategy of reducing the size of storage units that highly depends on physical factors or processing technologies, organic multi-valued resistive random access memory (ReRAM) devices have attracted more and more attention from scientists in the past decade or so, mainly considering their diversified processability, simple sandwich structure, and ultra-high data storage density (HDSD), etc. Since the ternary storage device based on small molecule materials was first reported in 2010, scientists have currently developed a series of functional materials to prepare multi-valued information storage devices, mainly including small molecule materials, polymer materials, organometallic complex materials, covalent organic framework (COF) materials, as well as transition metal oxide materials, graphene oxide materials, two-dimensional semiconductor materials, perovskite materials, etc.

[0003] Among all the above-mentioned multi-valued information storage materials, small molecule materials show the best potential in the next-generation ultra-high density information storage materials due to their advantages such as clear structure, simple synthesis, efficient purification, good crystallinity, excellent scalability, etc. However, there is still a large gap between the multi-valued information storage technology based on small molecule materials and practical applications. This is mainly because there are still some difficult-to-solve problems in the small molecule thin films obtained by processes such as spin coating: First, it is difficult to accurately predict the intermolecular interactions and packing modes in the thin film even for tailor-made small molecule materials; second, even after thermal annealing treatment of these small molecule thin films, the consistency between the internal molecular packing and the external surface morphology is still not ideal, and there will still be certain crystalline and non-crystalline regions in the thin film. These problems will in turn affect the effective transport of charge carriers in the thin film, leading to significant changes in device performance and unnecessary reliability failures. Summary of the Invention

[0004] Object of the Invention: The object of the present invention is to provide a molecular assembly method for organic D-A type multi-valued conjugated small molecules, which overcomes the problems of unclear molecular packing, inconsistent morphology, poor device stability and reproducibility in existing multi-valued storage devices.

[0005] Another object of the present invention is to provide an application of an assembly prepared by a molecular assembly method of organic D-A type multi-valued conjugated small molecules for ultra-high density information storage.

[0006] Technical Solution: A molecular assembly method for organic D-A type multi-valued conjugated small molecules of the present invention includes the following steps:

[0007] (1) Using 1,2-diaminobenzene and oxalic acid as raw materials, polyphosphoric acid as a catalyst, reacting in an alcohol solvent. After the reaction ends, cool, filter, wash, and vacuum dry to prepare a brown powdery solid, i.e., organic D-A type multi-valued conjugated small molecule, and the organic D-A type multi-valued conjugated small molecule is 6,6'-dinitro-1H,1'H-2,2'-bibenzo[d]imidazole;

[0008] (2) Disperse the organic D-A type multi-valued conjugated small molecule obtained in step (1) in an organic solvent, and use heating, stirring, and ultrasonic methods to completely dissolve it and form a clear and transparent solution to obtain an assembly solution;

[0009] (3) Drop the assembly solution prepared in step (2) on the surface of a clean indium tin oxide glass. After dropping, let it stand, and wait for the solvent to slowly volatilize naturally until the surface of the indium tin oxide glass is dry to obtain an assembly.

[0010] Further, in step (1), the 1,2-diaminobenzene is selected from one of 1,2-diamino-4-nitrobenzene, 1,2-diamino-4-nitrobenzene hydrochloride, and 1,2-diamino-4-nitrobenzene sulfate; the polyphosphoric acid is selected from one of ortho-polyphosphoric acid, iso-polyphosphoric acid, oligomeric phosphoric acid, and supramolecular polyphosphoric acid; the alcohol solvent is selected from one of 1,2-ethylene glycol, glycerol, 1,2-propanediol, 1,2-butanediol, and 1,4-butanediol.

[0011] Further, in step (1), the molar ratio of 1,2-diaminobenzene to oxalic acid is (2~5):1; the addition amount of polyphosphoric acid is 1%~5% mol of oxalic acid.

[0012] Further, in step (1), the reaction is carried out in an anhydrous and anaerobic environment, the reaction temperature is 150°C~180°C; the reaction time is 2 h~5 h.

[0013] Further, in step (1), wash the filter cake with hot water at 80°C~100°C, and the number of washing times is 3~5 times.

[0014] Further, in step (2), the organic solvent is selected from one of ethanol, dichloromethane, chloroform, tetrahydrofuran, dimethyl sulfoxide, and N,N-dimethylformamide.

[0015] Further, in step (2), the concentration of the assembly solution is 10 -5 ~10 -3 mol / L.

[0016] Further, in step (3), the environmental temperature of the indium tin oxide glass is 15°C to 30°C.

[0017] The present invention provides a method for synthesizing an organic D-A type multi-valent conjugated small molecule using the above method, and preparing an assembly based on the organic D-A type multi-valent conjugated small molecule.

[0018] The present invention provides an application of the above assembly as an ultra-high density information storage.

[0019] Beneficial effects: Compared with the prior art, the present invention has the following remarkable advantages: (1) The synthesis steps of the organic D-A type multi-valent conjugated small molecule of the present invention are simple, can be obtained by a one-step method, the required raw materials are simple and easy to obtain, and the operation is simple, which is very important for large-scale applications.

[0020] (2) The organic D-A type multi-valent conjugated small molecule of the present invention not only introduces two electron-withdrawing groups, nitro and imidazole, into the molecular backbone, but also introduces an N-H bond into the molecular bay area. On the basis of realizing multi-valence, it can induce the N-H…N hydrogen bond interaction between molecules, which is beneficial to the interaction and close packing mode of molecules, and ultimately beneficial to the free and effective transmission of charge carriers between active layers.

[0021] (3) The self-assembly method of the organic D-A type multi-valent conjugated small molecule of the present invention is simple and easy to operate. By dropping the prepared assembly solution on the glass surface, an assembly with a certain size and morphology can be obtained after the solvent has completely evaporated, improving the consistency of intermolecular packing.

[0022] (4) The assembly based on the organic D-A type multi-valent conjugated small molecule prepared by the present invention, through the electrical performance test of the conductive probe of the conductive atomic force microscope (C-AFM), compared with the commonly used "sandwich" device, the storage unit can be greatly reduced from the micron level to the nano level. On the basis of multi-valence, the device unit size can be further reduced, further improving the storage density of the information storage device and realizing ultra-high density information storage. Description of the Drawings

[0023] Figure 1Synthesis steps diagram of the organic D-A type multi-valued conjugated small molecule in Example 1;

[0024] Figure 2 1H-NMR spectrum diagram of the organic D-A type multi-valued conjugated small molecule in Example 1;

[0025] Figure 3 Theoretical simulation of the organic D-A type multi-valued conjugated small molecule in Example 1;

[0026] Figure 4 SEM diagram of the assembly formed by the self-assembly of the molecule in Example 18;

[0027] Figure 5 AFM diagram of the assembly formed by the self-assembly of the molecule in Example 18;

[0028] Figure 6 Electrical property diagram of the assembly prepared in Example 18 measured by conductive atomic force microscopy (C-AFM). Detailed implementation manners

[0029] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, so that those skilled in the art can better understand the present invention and be able to implement it, but the embodiments cited do not limit the present invention. Example 1

[0030] Synthesis of the organic D-A type multi-valued conjugated small molecule, the specific steps are as follows:

[0031] First, under a nitrogen atmosphere, 1,2-diamino-4-nitrobenzene (2.52 g, 0.02 mol), oxalic acid (0.90 g, 0.01 mol) and 1,2-propanediol (60 ml) were placed in a 100 ml round-bottom flask and stirred evenly, and then 100 mg (3% mol) of the catalyst - orthophosphoric acid was added thereto. The subsequent reaction was carried out at a temperature of 150 °C for 4 hours. After the reaction was completed, the reaction system was cooled to room temperature, filtered by suction, and then the filter cake was washed 3 times with hot water at 80 °C. Finally, the filter cake was placed in a vacuum drying oven and dried for 24 hours to obtain 2.41 g of a brown powdery solid, and its yield was calculated to be about 90%.

[0032] Appendix Figure 1 Synthesis route diagram of the D-A type multi-valued conjugated small molecule, Appendix Figure 3 Theoretical simulation diagram of the D-A type multi-valued conjugated small molecule, Appendix Figure 21H-NMR spectrum of the D-A type multi-valent conjugated small molecule material prepared in Example 1. From the 1H-NMR spectrum, it can be seen that the NMR peak at δ = 14.49 can be attributed to the N-H in the molecular bay area, and the peaks at δ = 7.83 - 8.60 are attributed to the hydrogen atoms on the aromatic ring. From the theoretical simulation diagram, it can be seen that there are also two electron-withdrawing groups with different intensities in the molecular skeleton, and the electron-withdrawing ability of the nitro group is stronger than that of imidazole. Example 2

[0033] The synthesis of the organic D-A type multi-valent conjugated small molecule is as follows:

[0034] First, under a nitrogen atmosphere, 1,2-diamino-4-nitrobenzene hydrochloride (3.98 g, 0.02 mol), oxalic acid (0.90 g, 0.01 mol), and 1,2-propanediol (60 ml) were placed in a 100 ml round-bottom flask and stirred evenly. Then, 100 mg (3% mol) of the catalyst, orthophosphoric acid, was added thereto. The subsequent reaction was carried out at a temperature of 150 °C for 4 hours. After the reaction was completed, the reaction system was cooled to room temperature, filtered by suction, and then the filter cake was washed 3 times with hot water at 80 °C. Finally, the filter cake was placed in a vacuum drying oven and dried for 24 hours to obtain 2.06 g of a brownish powder solid. The yield was calculated to be approximately 77%. Example 3

[0035] The synthesis of the organic D-A type multi-valent conjugated small molecule is as follows:

[0036] First, under a nitrogen atmosphere, 1,2-diamino-4-nitrobenzene (2.52 g, 0.02 mol), oxalic acid (0.90 g, 0.01 mol), and 1,2-ethylene glycol (60 ml) were placed in a 100 ml round-bottom flask and stirred evenly. Then, 100 mg (3% mol) of the catalyst, orthophosphoric acid, was added thereto. The subsequent reaction was carried out at a temperature of 150 °C for 4 hours. After the reaction was completed, the reaction system was cooled to room temperature, filtered by suction, and then the filter cake was washed 3 times with hot water at 80 °C. Finally, the filter cake was placed in a vacuum drying oven and dried for 24 hours to obtain 2.10 g of a brownish powder solid. The yield was calculated to be approximately 78%. Example 4

[0037] The synthesis of the organic D-A type multi-valent conjugated small molecule is as follows:

[0038] First, under a nitrogen atmosphere, 1,2-diamino-4-nitrobenzene (2.52 g, 0.02 mol), oxalic acid (0.90 g, 0.01 mol), and glycerol (60 ml) were placed in a 100-ml round-bottom flask and stirred evenly. Then, 100 mg (3% mol) of the catalyst, orthophosphoric acid, was added thereto. The subsequent reaction was carried out at a temperature of 150 °C for 4 hours. After the reaction was completed, the reaction system was cooled to room temperature, filtered by suction, and then the filter cake was washed 3 times with hot water at 80 °C. Finally, the filter cake was placed in a vacuum drying oven and dried for 24 hours to obtain 2.31 g of a brownish powder solid, and its yield was calculated to be approximately 86%. Example 5

[0039] The synthesis of the organic D-A type multi-valued conjugated small molecule is carried out as follows:

[0040] First, under a nitrogen atmosphere, 1,2-diamino-4-nitrobenzene (2.52 g, 0.02 mol), oxalic acid (0.90 g, 0.01 mol), and 1,2-propanediol (60 ml) were placed in a 100-ml round-bottom flask and stirred evenly. Then, 100 mg (3% mol) of the catalyst, oligophosphoric acid, was added thereto. The subsequent reaction was carried out at a temperature of 150 °C for 4 hours. After the reaction was completed, the reaction system was cooled to room temperature, filtered by suction, and then the filter cake was washed 3 times with hot water at 80 °C. Finally, the filter cake was placed in a vacuum drying oven and dried for 24 hours to obtain 1.98 g of a brownish powder solid, and its yield was calculated to be approximately 75%. Example 6

[0041] The synthesis of the organic D-A type multi-valued conjugated small molecule is carried out as follows:

[0042] First, under a nitrogen atmosphere, 1,2-diamino-4-nitrobenzene (2.52 g, 0.02 mol), oxalic acid (0.90 g, 0.01 mol), and 1,2-propanediol (60 ml) were placed in a 100-ml round-bottom flask and stirred evenly. Then, 100 mg (3% mol) of the catalyst, orthophosphoric acid, was added thereto. The subsequent reaction was carried out at a temperature of 180 °C for 4 hours. After the reaction was completed, the reaction system was cooled to room temperature, filtered by suction, and then the filter cake was washed 3 times with hot water at 80 °C. Finally, the filter cake was placed in a vacuum drying oven and dried for 24 hours to obtain 2.55 g of a brownish powder solid, and its yield was calculated to be approximately 95%. Example 7

[0043] The synthesis of the organic D-A type multi-valued conjugated small molecule is carried out as follows:

[0044] First, under a nitrogen atmosphere, 1,2-diamino-4-nitrobenzene (2.52 g, 0.02 mol), oxalic acid (0.90 g, 0.01 mol), and 1,2-propanediol (60 ml) were placed in a 100 ml round-bottom flask and stirred evenly. Then, 100 mg (3% mol) of the catalyst, orthophosphoric acid, was added thereto. The subsequent reaction was carried out at a temperature of 160 °C for 4 hours. After the reaction was completed, the reaction system was cooled to room temperature, filtered by suction, and then the filter cake was washed 3 times with hot water at 80 °C. Finally, the filter cake was placed in a vacuum drying oven and dried for 24 hours to obtain 2.47 g of a brownish powder solid, and its yield was calculated to be approximately 93%. Example 8

[0045] The synthesis of the organic D-A type multi-valued conjugated small molecule is as follows:

[0046] First, under a nitrogen atmosphere, 1,2-diamino-4-nitrobenzene (2.52 g, 0.02 mol), oxalic acid (0.90 g, 0.01 mol), and 1,2-propanediol (60 ml) were placed in a 100 ml round-bottom flask and stirred evenly. Then, 100 mg (3% mol) of the catalyst, orthophosphoric acid, was added thereto. The subsequent reaction was carried out at a temperature of 150 °C for 5 hours. After the reaction was completed, the reaction system was cooled to room temperature, filtered by suction, and then the filter cake was washed 3 times with hot water at 80 °C. Finally, the filter cake was placed in a vacuum drying oven and dried for 24 hours to obtain 2.42 g of a brownish powder solid, and its yield was calculated to be approximately 91%. Example 9

[0047] The synthesis of the organic D-A type multi-valued conjugated small molecule is as follows:

[0048] First, under a nitrogen atmosphere, 1,2-diamino-4-nitrobenzene (2.52 g, 0.02 mol), oxalic acid (0.90 g, 0.01 mol), and 1,2-propanediol (60 ml) were placed in a 100 ml round-bottom flask and stirred evenly. Then, 100 mg (3% mol) of the catalyst, orthophosphoric acid, was added thereto. The subsequent reaction was carried out at a temperature of 150 °C for 2 hours. After the reaction was completed, the reaction system was cooled to room temperature, filtered by suction, and then the filter cake was washed 3 times with hot water at 80 °C. Finally, the filter cake was placed in a vacuum drying oven and dried for 24 hours to obtain 2.01 g of a brownish powder solid, and its yield was calculated to be approximately 76%.

[0049] Example 10:

[0050] The synthesis of the organic D-A type multi-valued conjugated small molecule is as follows:

[0051] First, under a nitrogen atmosphere, 1,2-diamino-4-nitrobenzene (2.52 g, 0.02 mol), oxalic acid (0.90 g, 0.01 mol) and 1,2-propanediol (60 ml) were placed in a 100 ml round-bottom flask and stirred evenly. Then, 100 mg (3% mol) of the catalyst, orthophosphoric acid, was added thereto. The subsequent reaction was carried out at a temperature of 150 °C for 4 hours. After the reaction was completed, the reaction system was cooled to room temperature, filtered by suction, and then the filter cake was washed 3 times with hot water at 100 °C. Finally, the filter cake was placed in a vacuum drying oven and dried for 24 hours to obtain 2.22 g of a brown powdery solid. The yield was calculated to be approximately 84%.

[0052] Example 11:

[0053] The synthesis of the organic D-A type multi-valued conjugated small molecule is carried out as follows:

[0054] First, under a nitrogen atmosphere, 1,2-diamino-4-nitrobenzene (2.52 g, 0.02 mol), oxalic acid (0.90 g, 0.01 mol) and 1,2-propanediol (60 ml) were placed in a 100 ml round-bottom flask and stirred evenly. Then, 100 mg (3% mol) of the catalyst, orthophosphoric acid, was added thereto. The subsequent reaction was carried out at a temperature of 150 °C for 4 hours. After the reaction was completed, the reaction system was cooled to room temperature, filtered by suction, and then the filter cake was washed 3 times with hot water at 90 °C. Finally, the filter cake was placed in a vacuum drying oven and dried for 24 hours to obtain 2.36 g of a brown powdery solid. The yield was calculated to be approximately 89%.

[0055] Example 12:

[0056] The synthesis of the organic D-A type multi-valued conjugated small molecule is carried out as follows:

[0057] First, under a nitrogen atmosphere, 1,2-diamino-4-nitrobenzene (2.52 g, 0.02 mol), oxalic acid (0.90 g, 0.01 mol) and 1,2-propanediol (60 ml) were placed in a 100 ml round-bottom flask and stirred evenly. Then, 100 mg (3% mol) of the catalyst, orthophosphoric acid, was added thereto. The subsequent reaction was carried out at a temperature of 150 °C for 4 hours. After the reaction was completed, the reaction system was cooled to room temperature, filtered by suction, and then the filter cake was washed 4 times with hot water at 80 °C. Finally, the filter cake was placed in a vacuum drying oven and dried for 24 hours to obtain 2.39 g of a brown powdery solid. The yield was calculated to be approximately 90%.

[0058] Example 13:

[0059] Synthesis of organic D-A type multi-valued conjugated small molecules is as follows:

[0060] First, under a nitrogen atmosphere, 1,2-diamino-4-nitrobenzene (2.52 g, 0.02 mol), oxalic acid (0.90 g, 0.01 mol) and 1,2-propanediol (60 ml) were placed in a 100 ml round-bottom flask and stirred evenly. Then, 100 mg (3% mol) of the catalyst, orthophosphoric acid, was added thereto. The subsequent reaction was carried out at a temperature of 150 °C for 4 hours. After the reaction was completed, the reaction system was cooled to room temperature, filtered by suction, and then the filter cake was washed 5 times with hot water at 80 °C. Finally, the filter cake was placed in a vacuum drying oven and dried for 24 hours to obtain 2.35 g of a brown powdery solid, and its yield was calculated to be about 89%.

[0061] Example 14:

[0062] Synthesis of organic D-A type multi-valued conjugated small molecules is as follows:

[0063] First, under a nitrogen atmosphere, 1,2-diamino-4-nitrobenzene (6.30 g, 0.05 mol), oxalic acid (0.90 g, 0.01 mol) and 1,2-propanediol (60 ml) were placed in a 100 ml round-bottom flask and stirred evenly. Then, 100 mg (3% mol) of the catalyst, orthophosphoric acid, was added thereto. The subsequent reaction was carried out at a temperature of 150 °C for 4 hours. After the reaction was completed, the reaction system was cooled to room temperature, filtered by suction, and then the filter cake was washed 3 times with hot water at 80 °C. Finally, the filter cake was placed in a vacuum drying oven and dried for 24 hours to obtain 2.48 g of a brown powdery solid, and its yield was calculated to be about 94%.

[0064] Example 15:

[0065] Synthesis of organic D-A type multi-valued conjugated small molecules is as follows:

[0066] First, under a nitrogen atmosphere, 1,2-diamino-4-nitrobenzene (3.78 g, 0.03 mol), oxalic acid (0.90 g, 0.01 mol), and 1,2-propanediol (60 ml) were placed in a 100 ml round-bottom flask and stirred evenly. Then, 100 mg (3% mol) of the catalyst, orthophosphoric acid, was added thereto. The subsequent reaction was carried out at a temperature of 150 °C for 4 hours. After the reaction was completed, the reaction system was cooled to room temperature, filtered by suction, and then the filter cake was washed 3 times with hot water at 80 °C. Finally, the filter cake was placed in a vacuum drying oven and dried for 24 hours to obtain 2.45 g of a brownish powder solid. The yield was calculated to be approximately 92%.

[0067] Example 16:

[0068] The synthesis of the organic D-A type multi-valued conjugated small molecule is carried out as follows:

[0069] First, under a nitrogen atmosphere, 1,2-diamino-4-nitrobenzene (3.78 g, 0.03 mol), oxalic acid (0.90 g, 0.01 mol), and 1,2-propanediol (60 ml) were placed in a 100 ml round-bottom flask and stirred evenly. Then, 33 mg (1% mol) of the catalyst, orthophosphoric acid, was added thereto. The subsequent reaction was carried out at a temperature of 150 °C for 4 hours. After the reaction was completed, the reaction system was cooled to room temperature, filtered by suction, and then the filter cake was washed 3 times with hot water at 80 °C. Finally, the filter cake was placed in a vacuum drying oven and dried for 24 hours to obtain 2.10 g of a brownish powder solid. The yield was calculated to be approximately 79%.

[0070] Example 17:

[0071] The synthesis of the organic D-A type multi-valued conjugated small molecule is carried out as follows:

[0072] First, under a nitrogen atmosphere, 1,2-diamino-4-nitrobenzene (3.78 g, 0.03 mol), oxalic acid (0.90 g, 0.01 mol), and 1,2-propanediol (60 ml) were placed in a 100 ml round-bottom flask and stirred evenly. Then, 163 mg (5% mol) of the catalyst, orthophosphoric acid, was added thereto. The subsequent reaction was carried out at a temperature of 150 °C for 4 hours. After the reaction was completed, the reaction system was cooled to room temperature, filtered by suction, and then the filter cake was washed 3 times with hot water at 80 °C. Finally, the filter cake was placed in a vacuum drying oven and dried for 24 hours to obtain 2.50 g of a brownish powder solid. The yield was calculated to be approximately 94%.

[0073] Example 18:

[0074] Self-assembly of organic D-A type multi-valued conjugated small molecules is as follows:

[0075] First, place indium tin oxide (ITO) glass in an aqueous solution of washing powder and ultrasonicate for 30 minutes to remove oily substances on the surface, and then carefully scrub until there are no obvious particulate contaminants on the glass surface. Secondly, place the washed ITO glass in deionized water, acetone, and glycerol solvents and ultrasonicate each for 25 minutes. Finally, dry the clean ITO glass with nitrogen in a clean room and place it horizontally in a fume hood for standby.

[0076] Then, weigh a certain mass of organic D-A type multi-valued conjugated small molecules and disperse them in 10 ml of tetrahydrofuran solvent to control the concentration at 10 -4 mol / L, and ultrasonicate to completely dissolve them to form a clear and transparent solution system. Secondly, use a syringe to extract 5 ml of the solution system, and then install an organic filter head with a diameter of 0.22 μm on the syringe. Slowly drop this solution system on the surface of the ITO glass until the surface of the ITO glass is completely covered. Control the room temperature at 25 °C and wait for it to fully volatilize until the solvent has completely volatilized, then an assembly formed by N-H…N hydrogen bond induction can be obtained.

[0077] Appendix Figure 4 is the SEM image of the assembly formed by the molecular self-assembly of Example 18. Appendix Figure 4 The (a), (b), (c), and (d) in it are the SEM images of the assembly at different pixel sizes respectively. Appendix Figure 5 is the AFM image of the assembly formed by the molecular self-assembly of Example 18. Appendix Figure 5 In the figure (a) is the atomic force microscope image of the assembly, (b) is the 3D atomic force microscope image of the assembly, and (c) is the corresponding thickness image of the assembly. It can be seen from the pictures that the molecular self-assembly forms a structure with a regular rectangular morphology.

[0078] Example 19:

[0079] Self-assembly of organic D-A type multi-valued conjugated small molecules is as follows:

[0080] First, place indium tin oxide (ITO) glass in an aqueous solution of washing powder and ultrasonicate for 30 minutes to remove oily substances on the surface, and then carefully scrub until there are no obvious particulate contaminants on the glass surface. Secondly, place the washed ITO glass in deionized water, acetone, and glycerol solvents and ultrasonicate each for 25 minutes. Finally, dry the clean ITO glass with nitrogen in a clean room and place it horizontally in a fume hood for standby.

[0081] Then, weigh a certain mass of the organic D-A type multi-valent conjugated small molecule and disperse it in 10 ml of tetrahydrofuran solvent to control its concentration to 10 -5 mol / L, and ultrasonically dissolve it to form a clear and transparent solution system. Secondly, draw 5 ml of the solution system with a syringe, and then install an organic filter head with a diameter of 0.22 μm on the syringe. Slowly drip this solution system onto the surface of the ITO glass until the surface of the ITO glass is completely covered. Control the room temperature at 25°C, and wait for it to fully volatilize until the solvent is completely volatilized, then an assembly induced by N-H…N hydrogen bonds can be obtained.

[0082] Example 20:

[0083] The self-assembly of the organic D-A type multi-valent conjugated small molecule is carried out as follows:

[0084] First, place the indium tin oxide (ITO) glass in an aqueous solution of washing powder and ultrasonically treat it for 30 minutes to remove the oily substances on the surface, and then carefully scrub it until there are no obvious particulate contaminants on the glass surface. Secondly, place the washed ITO glass in deionized water, acetone, and glycerol solvents and ultrasonically treat it for 25 minutes respectively. Finally, dry the clean ITO glass with nitrogen in a clean room and place it horizontally in a fume hood for standby.

[0085] Then, weigh a certain mass of the organic D-A type multi-valent conjugated small molecule and disperse it in 10 ml of tetrahydrofuran solvent to control its concentration to 10 -3 mol / L, and ultrasonically dissolve it to form a clear and transparent solution system. Secondly, draw 5 ml of the solution system with a syringe, and then install an organic filter head with a diameter of 0.22 μm on the syringe. Slowly drip this solution system onto the surface of the ITO glass until the surface of the ITO glass is completely covered. Control the room temperature at 25°C, and wait for it to fully volatilize until the solvent is completely volatilized, then an assembly induced by N-H…N hydrogen bonds can be obtained.

[0086] Example 21:

[0087] The self-assembly of the organic D-A type multi-valent conjugated small molecule is carried out as follows:

[0088] First, place the indium tin oxide (ITO) glass in an aqueous solution of washing powder and ultrasonically treat it for 30 minutes to remove the oily substances on the surface, and then carefully scrub it until there are no obvious particulate contaminants on the glass surface. Secondly, place the washed ITO glass in deionized water, acetone, and glycerol solvents and ultrasonically treat it for 25 minutes respectively. Finally, dry the clean ITO glass with nitrogen in a clean room and place it horizontally in a fume hood for standby.

[0089] Then, weigh a certain mass of the organic D-A type multi-valent conjugated small molecule and disperse it in 10 ml of tetrahydrofuran solvent, controlling its concentration to be 10 -4 mol / L, and ultrasonically dissolve it until it is completely dissolved to form a clear and transparent solution system. Secondly, use a syringe to extract 5 ml of the solution system, and then install an organic filter head with a diameter of 0.22 μm on the syringe. Slowly drip this solution system onto the surface of the ITO glass until the surface of the ITO glass is completely covered. Control the room temperature at 15 °C, and wait for it to fully volatilize until the solvent is completely volatilized to obtain the assembly formed by N-H…N hydrogen bond induction.

[0090] Example 22:

[0091] Self-assembly of the organic D-A type multi-valent conjugated small molecule is carried out as follows:

[0092] First, place the indium tin oxide (ITO) glass in an aqueous washing powder solution and ultrasonically wash for 30 minutes to remove the oily substances on the surface, and then carefully scrub until there are no obvious particulate contaminants on the glass surface. Secondly, place the washed ITO glass in deionized water, acetone, and glycerol solvents and ultrasonically wash for 25 minutes each. Finally, dry the clean ITO glass with nitrogen in a clean room and place it horizontally in a fume hood for standby.

[0093] Then, weigh a certain mass of the organic D-A type multi-valent conjugated small molecule and disperse it in 10 ml of tetrahydrofuran solvent, controlling its concentration to be 10 -4 mol / L, and ultrasonically dissolve it until it is completely dissolved to form a clear and transparent solution system. Secondly, use a syringe to extract 5 ml of the solution system, and then install an organic filter head with a diameter of 0.22 μm on the syringe. Slowly drip this solution system onto the surface of the ITO glass until the surface of the ITO glass is completely covered. Control the room temperature at 30 °C, and wait for it to fully volatilize until the solvent is completely volatilized to obtain the assembly formed by N-H…N hydrogen bond induction.

[0094] Example 23:

[0095] Self-assembly of the organic D-A type multi-valent conjugated small molecule is carried out as follows:

[0096] First, place the indium tin oxide (ITO) glass in an aqueous washing powder solution and ultrasonically wash for 30 minutes to remove the oily substances on the surface, and then carefully scrub until there are no obvious particulate contaminants on the glass surface. Secondly, place the washed ITO glass in deionized water, acetone, and glycerol solvents and ultrasonically wash for 25 minutes each. Finally, dry the clean ITO glass with nitrogen in a clean room and place it horizontally in a fume hood for standby.

[0097] Then, a certain mass of the organic D-A type multi-valued conjugated small molecule was weighed and dispersed in 10 ml of ethanol solvent to control its concentration to be 10 -4 mol / L, and ultrasonic treatment was used to completely dissolve it to form a clear and transparent solution system. Secondly, 5 ml of the solution system was drawn with a syringe, and then an organic filter head with a diameter of 0.22 μm was installed on the syringe. The solution system was slowly dropped on the surface of the ITO glass until the surface of the ITO glass was completely covered. The room temperature was controlled at 25 °C, and after it was fully volatilized until the solvent was completely volatilized, an assembly formed by N-H…N hydrogen bond induction could be obtained.

[0098] The assemblies formed by the molecular self-assembly of Examples 19-23 were also tested and all formed structures with regular rectangular morphologies.

[0099] Test example:

[0100] For the electrical property test of conductive atomic force microscopy (C-AFM), the specific steps are as follows:

[0101] The prepared ITO glass with a regular morphology of Example 18 was placed on the sample stage of Bruker atomic force microscope Nasoscope V Multimode 8. The conductive probe was installed on a special conductive needle holder, and a forward and reverse scanning voltage of -10 to 10 V was applied to the conductive probe, and its electrical properties were recorded.

[0102] Appendix Figure 6 Shown is the electrical property of the assembly measured by conductive atomic force microscopy (C-AFM). The results show that under the reverse scanning voltage of -10 to 10 V, the assembly exhibits obvious ternary storage performance. At the same time, the tip size of the conductive probe is only about 20 nm, which is much smaller than 120 μm in the "sandwich" device unit. Based on the realization of multi-valued storage, the invention can further improve the storage density of the device by coordinating the strategy of reducing the device unit size, and has potential application value.

[0103] Obviously, the above embodiments are only examples given for clear illustration and are not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to enumerate all the implementation manners here. And the obvious changes or modifications derived therefrom are still within the protection scope of the present invention.

Claims

1. A molecular assembly method of an organic D-A type multi-valued conjugated small molecule, characterized in that It includes the following steps: (1) Using 1,2-diamino-4-nitrobenzene compounds and oxalic acid as raw materials, polyphosphoric acid as a catalyst, reacting in an alcohol solvent. After the reaction is completed, cool, filter, wash, and vacuum dry to prepare a brownish powder solid, namely the organic D-A type multi-valent conjugated small molecule, and the organic D-A type multi-valent conjugated small molecule is 6,6'-dinitro-1H,1'H-2,2'-bibenzo[d]imidazole; the 1,2-diamino-4-nitrobenzene compound is selected from one of 1,2-diamino-4-nitrobenzene, 1,2-diamino-4-nitrobenzene hydrochloride, and 1,2-diamino-4-nitrobenzene sulfate; (2) Disperse the organic D-A type multi-valent conjugated small molecule obtained in step (1) in an organic solvent, and use heating, stirring, and ultrasonic methods to completely dissolve it and form a clear and transparent solution to obtain an assembly solution; the organic solvent is tetrahydrofuran; (3) Drop the assembly solution prepared in step (2) on the surface of a clean indium tin oxide glass. After dropping, let it stand, and wait for the solvent to slowly volatilize naturally until the surface of the indium tin oxide glass is dry to obtain an assembly.

2. The molecular assembly method of the organic D-A type multi-valued conjugated small molecule according to claim 1, characterized in that, In step (1), the polyphosphoric acid is selected from one of ortho-polyphosphoric acid, iso-polyphosphoric acid, oligomeric polyphosphoric acid, and supramolecular polyphosphoric acid; the alcohol solvent is selected from one of 1,2-ethylene glycol, glycerol, 1,2-propanediol, 1,2-butanediol, and 1,4-butanediol.

3. The molecular assembly method of the organic D-A type multi-valued conjugated small molecule according to claim 1, characterized in that, In step (1), the molar ratio of 1,2-diaminobenzene to oxalic acid is (2~5):1; the addition amount of polyphosphoric acid is 1%~5% mol of oxalic acid.

4. The molecular assembly method of the organic D-A type multi-valued conjugated small molecule according to claim 1, characterized in that In step (1), the reaction is carried out in an anhydrous and anaerobic environment, and the reaction temperature is 150°C~180°C; the reaction time is 2 h~5h.

5. The molecular assembly method of the organic D-A type multi-valued conjugated small molecule according to claim 1, characterized in that, In step (1), wash the filter cake with hot water at 80°C~100°C, and the number of washing times is 3~5 times.

6. The molecular assembly method of the organic D-A type multi-valued conjugated small molecule according to claim 1, wherein In step (2), the concentration of the assembly solution is 10 -5 ~10 -3 mol / L.

7. The molecular assembly method of the organic D-A type multi-valued conjugated small molecule according to claim 1, characterized in that, In step (3), the environmental temperature where the indium tin oxide glass is located is 15°C~30°C.

8. An assembly prepared by the molecular assembly method of the organic D-A type multi-valent conjugated small molecule according to any one of claims 1-7.

9. Application of the assembly according to claim 8 in ultra-high density information storage.

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